Pavement.



* No. 693,192. Y Patented Feb. ",1902.4

^ H. G. voLKMA.; PAVEMENT.

(Applition med May 1e, m01.)

kno-Model.) 2 sheefssheef f F/. 2, y y l INVENTOR;

- l By Attorneys,

, vQTKN'Es-SES;

" n 'a 'uommusvm *mun-moua 0:7 :8:13a suman Bru H. G. VLKMAB.

PAVEMENT.

, (Application med ngi-16, 1901.)

(No umm.) u 2 sums-#sheet 2.

'WITNESSIEs; 5M

UNITED STAT-ns PATENT OFFICE.

HENRY G. VOJKMAR, OF NEW YORK, N. Y.

PAVEMENT.

SPECIFICATION forming part of Letters'Paten't No. 693,192, dated February 11, 1902. i Application filed May 16, 1901. Serial No. 60,521. (No model.) i

To all when?, t may concern:

Be it known that I, HENRY G. VOLKMAR,

a citizen of the United States, residing in they i borough' of Manhattan, city, county/,and State' of New York, have invented` certain new and' useful Improvementsin Pavenients, of which the following is a specification.

My invention provides improvements in pavements of asphalt or similar plastic material, whereby the pavement is maintainedv in goodcondition for a considerable time and whereby the wear of traflic: and the consequent expense for repairs is very slight.

In asphalt pavements as generally constructed at present there is rapiddeterioration, especially where the trafficis heavy, the

surface wearing into holes and ruts, whichV the' point at which the load is concentrated, but causes it tovbulge at neighboring pointsA and to have a lateral movement which is always in excess in the downward-direction and which accumulates at the sides or gutters.4 By means of my invention the body of the asphalt is divided into small and substantially independent sections, so that the pressure due to a load concentrated at any point is localized and the material is prevented from spreading orcreeping.

My invention provides also various improvements in detail, as hereinafter set forth.

Referring to the accompanying drawings, illustrating an embodiment of my invention, Figure l shows in plan a system of frames for usein my improved pavements in the positions which they occupy in use, but with the plastic material omitted. Fig. 2 is a section, on an enlarged scale, on the line 2 2 of Fig. l, the plastic material being omitted here also, but its surface being shown by a dotted Fig. 3 is a section on the line 3 3 of sible.v modifications of the bar illustrated in l l vFig-4f. Fig. 6 is a perspective of an anchor.

Fig. 7 is a horizontal section through an anchor and the frames connected thereto on the line 7 7 of Fig.

tively, along one of thebolts connecting adjacent frames, showing especially the manner of` locking the same.

In the preferred form of my invention the division of the plastic material into independent sections is accomplished by embedding in the plastic materialastiffening-frame comprising wrought-metal bars having stiffenin gribs, whereby they are adapted to resist lateral deiection, so as to resist lateral transmission of vertical pressures on the asphalt. Preferably the stiffening-frame is slightly below the surface of the plastic material, so that without losing its localizing effect it permits of having a continuous surface common to each of the substantiallyindependent sections into which the body of plastic material is divided. The bars forming the divisions i Figs. 8 and 9 area 1ongi'" `tudinal section andl an end View, respecbetween the several sections are made quite stiff transversely, so as to resist lateral dcflection and prevent to a great degree the transmission of lateral pressure from one section to the next; Preferably the frame which I employ is madeup of a number of individual frames, each being. completeand self-contained, so as to serve its purpose in dividing the plastic'material in that part of the pavement in which it lies independently of the other individual frames. By reason of this construction, also, when the pavement is inj ured at one point it can be taken up entirely, the stiffening-frame as Well as the plastic body, over the space covered-by one of the individual sections without disturbing the adjacent portions of thepavement.

Referring now to the drawings, A indicates a plastic material forming the body of the pavement and which may be laid upon any suitable foundation, such as the usual concrete foundation B. Embedded in the plastic material A is a frame, preferably made in individual sections C. The frame is prefer=` IOO corners either by a lapped joint or by means' of an angle-iron, as shown at C2. The internal bars D of each of the individual frames C C, and which form the dividing-walls between the adjacent independent sections of` the plastic material, are preferably arranged diagonally and joined at their ends, as by bending and riveting, to the side and end bars. By the use of this form of connection the tendency of the bars to turn over under the lateral strains to which they are subjected is eiliciently resisted. Preferably, also, to unite the ent-ire frame strongly one or more tiebars E may be employed, running transversely of the hars D.

IVhere the bar E passes through the bars D near the middle of the latter, the bars D are preferably stilfened laterallyas for example, by means of sleeves F, threaded on the bar E and forming braces between the adjacent bars D and spacing said bars apart.

In order to preventthe rockin ofthe frames C by an eccentric load, I may anchor them at each corner and preferably at an intermediate point on ltheir long side. The anchor which I prefer to use has also the function of uniting the several frames which meet at a common point immediately above the anchor. Such anchor is preferably embedded in the base or foundation of concrete and projects above such base for attachment to the frame. I'Vhere the frames are laid so as to break joints with each other, as shown in Fig. l, a single anchor maybe attached to three frames. As shown in Figs. 3 and G, the preferred coustruction of my anchor includes an anchorplate G, a connecting-plate I-I, preferably of U shape, so as to permit of attachment to separatev frames C C, and one or more supporting-plates J or similar means upon which the frames C may be supported at a greater or less distance above the anchor-plate G, according to the depth to which it is desired to bury the plate G in the base B. The mode of assembling these parts will be referred to hereinafter. I prefer also to provide an additional rigid connection between the individual self-contained frames C at points intermediate of the anchor-plates, which serves to resist in part the lateral strain due to a load upon the plastic material between adjacent frames. Such connection may consist, for example, of bolts K and spacers or sleeves Il, Fig. l, the former preventing relative movement in one direction and the latter preventing movement in the oppositedirection.

eeaiea In order to secure considerable stiffness in the bars O of my frame, so as to resist lateral deflection without using unnecessarily heavy material, I prefer to employ a bar having a considerable distance between its extreme right and left hand points, as shown by the distance x in Fig. 4. At the Sametime I lind it useful to obtain this result by forming a sort of tongue M on one side and groove N on the other side of the bar, which tongue and groove may of course be varied considerably in outline, the groove of the form shown in Fig. 4 being cheap to roll and very efficient. The form shown in Fig. 5, however, in which the several tongues are shown by M M2 M3 and the several grooves by N' N2 N3, or any one of various other forms will obviously serve the purpose. By reason of the shape of the bar, as shown in Fig. Li, the plastic material forms a tongue A in connection with the groove N and a groove A2 in con' nection with the tongue M, which clfectually resist-s any tendency to relative movement of the plastic material and the bar in a vertical direction.

In the construction of a pavement embodying in detail all the improvements above set forth I proceed as follows: The base of the pavement will consist of any suitable foundation laid in a well -known manner on the earth and, according to the customary practice, having a curved upper surface. IVhere the upper surface of the base Bis curved, the frame C will be correspondingly curved; but it will be understood that these parts may be plane or that my improved pavement may be employed on any other suitable base--such, for example,as a bridgefloor-the foundation being modified to suit the special circum stances. Before the final layers of concrete are applied to bring the base B up to its proper grade the anchor-plate G is set in po sition so that the upper edge of the supporting-plates J are at the intended surface of the base, after which the concrete is brought up to grade, as usual. The sections C are then laid on the baseB, the side bars resting upon the supporting-plates J and being fastened, as by bolts P, to the connecting-plates H, which are attached, as by riveting, to the anchorplates G. The asphalt or similar plastic material is then filled in both within the frames C and in the space between the frames and to a height slightly above the upper edge of the frames, after which it may be rolled in the usual way to bring it to the desired evenness.

By reason of the independence of the various comparativelysmallsections into which my improved pavement is divided its life is very much longer than that of previous pavements, and it can stand very much heavier traffic without injury. There is no percep tible creeping. As is well known, the actual wear upon an asphalt surface is extremely slight, even under the heaviest traffic, the extensive repairs which the present asphalt lOO IIO

Vhole is rapidly enlarged, so that the hole is soon so deep and wide as to imperatively de-` mand repair. When a hole appears in the upper surface of my improved pavement, it cannot extend to a depth greater than thedepth of asphalt vabove the frame. v The members of the frame of my improved pavement are preferably so close together that wheels of ordinary size always bear substantially directly on at least one of the framemembers, so that the upper crust is supported at all points. Even when the crust is broken at a single point the edges of the hole are supported by` the frame, so that the widening of the hole is much less rapid than where the edges of the hole are supported only by the comparatively soft asphalt underneath. V.Also with my pavement the hole cannot wear vdeeper than the depth of the upper edges of the frames below the surface of the pavement, and after a considerable space has been worn to such a depth it is a very simplekkmatter to rebuild the worn parts and bring them up to their original surface.

The frame in my improved pavement thus' not only confines the plastic material into small substantially independent sections, so as to prevent lateral yielding, but serves itself to transmit the loads to the foundation ina direct vertical line and by reason of its plane bearing to distribute concentrated loads over comparatively Wide areas of the foundation.

By the use of wrought-metal bars stiffened against lateral deflection I secure any desired amount of resistance to vertical pressures, freedom from breakage under shock, frost, or the like, a pavement which is chiefly asphalt, so as to have all the advantages of a solidasphalt pavement,'and a stiffness laterally which prevents deterioration due to the plasticity of the asphalt.

By reason of the mode of operation described the depth of concrete under the, plas tic material does not need to be so great as in pavements Where a concentrated load is supported only upon a small area of the concrete foundation. This foundation may therefore be either of considerable depth throughout, as shown in Fig. 2, or of scarcely greater depth in general than that of the plastic material, as shown in Fig. 3, being made somewhat deeper immediately under the anchors, so as to give them a firm support.

There is always considerable jarring of the frames and their connections, and for this purpose it may be found advisable to lock thel bolts-#such as K, E, or P-which are used to,

connect the various parts A very convenient form of nut for preventing the loosening of these bolts is shown in Figs. 8 and 9 applied to the bolt K. In this construction the nut Q is preferably made of vsoft iron and is provided at its outer face with any desired number of projecting lugs R of preferably triangular cross-section, vwhich are adapted to be bent down, as by the blow of a hammer,

and fitted into a groove S in the end of the bolt after the nuts have' been screwed home.

The greater the number of lugs R on the nut the nicer the adjustment which cauvbe obtained and the more often the same nut can be used.` In order to unscrew the nut, the lug R can be very quicklyand easily cut off, the

nut being capable of reuse with any one of the remaining lugs. This locking mechanism is of especial use in my improved pavement,

because of the continual jarringto which itk is subjected and the invisibility andinaccessibility of the nuts for inspection or for tightening them when they are loosened.

It will be apparent that the advantages of my improved pavement may be obtained Without adhering exactly to the specific embodiment shown. l

Various modifications in the details and arrangement of the parts may be made without departure from the spirit of my invention, and various alterations of particular elements may be possible without sacrificing the advantages of other elements thereof. be understood, therefore, that I do not limit myselfto the specificA embodiment shown and described. Y i

I claim as my inventionl. In a pavement, the combination ofa body of asphalt, and a stiffening-frame open at the top and bottom and embedded in said asphalt, A said frame comprising Wrought metal bars having stiffening-ribs wherebythey are adapted toresist lateral deflection so that the asphalt is divided into substantially independent sections so as to resist lateral transmis'- Y sion of vertical pressures on said asphalt.

2. In a pavement, the combinationof a body of asphalt, and a stiffening-frame open at the top and bottom and embedded in said asphalt, said frame comprising wroughtmetal bars having stiffening-ribs whereby they are adapted to resist lateral .deflection so that the asv phalt is divided into substantially independent sectionsvso as to resist lateral transmis-y sion of vertical pressures on said asphalt, and said frame being below the snrfaceof said asphalt whereby said independent sections have a common continuous surface. v

3. In a pavement, the combination of a body of asphalt, and a stilfening-frame open at the top and bottom and'embedded in said asphalt, said frame comprising side bars, end bars and internal bars, the latter being of wrought metal and having stiening ribs, whereby they are adapted to resist lateral deflection It winA los IIO

so that the asphalt is divided into substantially independent sections so as to resist lateral transmissionof vertical pressures on said asphalt;

4. In a pavement, the combination of a body of asphalt, and a stiffening-frame open at the top and bottom and embedded in said asphalt, said frame comprising side bars, end bars and internal bars, the latter being of wrought metal and having stiffening ribs whereby they are adapted to resist lateral deiiection so that the asphalt is divided into substan-v tially independent sections so as to resist lateral transmission of vertical pressures on said asphalt, and braces between said internal bars for bracing the same transversely.

5. In a pavement, the combination ofa body ofasphalt, and a stiffening-frame open at the top and bottom and embedded in said asphalt, said frame comprising side bars, end bars and internal bars, the latter running crosswise of the side bars and being bent at their ends parallel to said side bars, and said bent ends being fastened to said side bars.

6. In apavement, the combination of a body of asphalt, and a stiffeningframe embedded therein, said frame comprising plain side bars and end bars and additional internal wrought-metal bars O having tongues M and grooves N whereby said bars are stiffencd against lateral deflection so as to resist lateral transmission of vertical pressures on said asphalt and are interlocked with said asphalt so as to resist relative vertical movement of said frame and said asphalt.

7. In apavement, the combination ot' a body of asphalt, and a stieningframe embedded therein, said frame comprising plain side bars and end bars and additional internal bars O running crosswise of the side bars and being bent at their ends parallel `to said side bars, and said bent ends being fastened to said side bars, said bars O having tongues M and grooves N whereby said bars are strengthened against lateral detlection so as to resist lateral transmission of vertical pressures on said asphalt and whereby said bars are interlocked with said asphalt so as to resist relative vertical movement of said frame and said asphalt.

S. In an asphalt pavement, the combination of an asphalt body and a stiffening-frame embedded therein, said frame being open at the top and bottom and comprising side and end bars, diagonal internal wrought-metal bars connecting said side and end bars, and a diagonal tie-rod arranged transversely of said internal bars, said bars having stiffening-ribs whereby they are adapted. to resist lateral deliection so that the asphalt is divided into substantially independent sections so as to resist lateral transmission of vertical pressures on said asphalt.

9. In an asphalt pavement, the combination of an asphalt body, complete self-contained stiffening-frames open at the top and bottom and embedded in said asphalt body below the surface thereof, the adjacent frames being detachably connected to each other.

10. In an asphalt pavement, the combnation of a concrete base, an asphalt top layer, a series of frames embedded in said asphalt side by side, and anchors fastened to said frames at adjacent edges thereof and embedded in said concrete base.

11. In an asphalt pavement, the combination of an asphalt body, a frame therein, and an anchor for said frame comprising an an Chor-plate, means for supporting saidframe above said anchor-plate, and means forattaching said frame to said anchor-plate above the latter.

12. In an asphalt pavement, the combination of an asphalt body, a frame therein, and an anchor for said frame comprising an auchor-plate G, a connecting-plate H adapted for attachment to said frame, and a supporting-plate adapted to support said frame above said plate.

13. An anchor for use in anchoring frames in pavements or the like comprising an an Chor-plate, means for supporting said frame above said plate, and means for attaching said frame to said anchor-plate above the latter.

14. An anchor for use in anchoring frames in pavements or the like comprising an anL Chor-plate, means for supporting said frame above said plate, and means attached to said plate and adapted for attachment to said frame.

15. An anchor for use in anchoring frames in pavements or the like comprising an anchor-plate, a connectingplate and a supporting-plate adapted to support a frame above said anchor-plate.

16. In an asphalt pavement, the combination of an asphalt body, complete self-contained stilening-frames embedded therein below the surface thereof, and breaking joints With each other, and an anchor attached to each of three frames at their meeting-point.

In witness whereof I have hereunto signed my name in the presence of two subscribing witnesses.

HENRY G. VOLKMAR.

Witnesses:

DOMINGO A. UsINA, 'FRED WHITE.

IOO 

